Breast Lumps and Lesions

Introduction

Breast lumps are a very common complaint for women of all ages. Breast lumps may occur spontaneously or gradually and may be accompanied by other symptoms such as breast pain, changes in the skin or changes in the nipple. A breast lump may or may not be noticeable to the patient; normal breast tissue can be quite lumpy in some women and some lumps can be small or located deep in the breast. Special tests such as a mammogram often detect breast lumps that cannot be felt. Over 90% of breast lumps are caused by benign breast disease, a range of non-cancerous conditions. If you are concerned about a breast lump, seek medical advice for further examination by a doctor.

Incidence of breast lumps and lesions

Breast lumps are a common finding in women of all ages, but are particularly common during the reproductive years (from first menstruation until menopause). One study examined 40 to 69 year old women presenting with breast complaints – 40% of these were for breast lumps or lumpiness. In those complaining of a lump, breast cancer was found in 11% of patients.

Breast cancer is the most common cancer in Australian women (excluding skin cancers) and constitutes 27.7% of all cancer diagnoses in women. In Australia, 35 women are diagnosed with breast cancer every day. Rates of breast cancer are highest in the age group 60–64, but can affect women of all ages. Two out of three breast cancers are diagnosed in women aged 40–69. By the age of 75, 1 in 11 Australian women will be diagnosed with breast cancer. While research on breast cancer in Indigenous women is more limited, they are half as likely to be diagnosed with breast cancer as non-Indigenous women.

Causes of breast lumps

Benign causes of breast lumps

Having a breast lump does not automatically mean a patient has breast cancer, as only 11% of people presenting with breast lumps turn out to have breast cancer. Additionally, many breast cancers are localised and can be treated effectively if diagnosed early. Most breast lumps are benign breast disease, a range of conditions that can cause breast lumps but are not cancerous. However, some benign breast diseases are associated with a slightly increased risk of cancer in the future, depending on that patient’s medical history, family history and risk factors. See your doctor for further advice and appropriate investigations for a breast lump.

The following conditions are common, benign causes of breast lumps and do not increase your risk of breast cancer in the future.

Breast cyst – blocked ducts in the breast create a small, fluid-filled sac – these are common around the time of menopause. They can sometimes be painful, and are easily managed by drainage with a needle;

Mastitis – usually due to an infection, the breast develops an area of inflammation that can be hard, red or tender. They are common during breastfeeding and can range from simple infections to complicated abscesses that require aggressive treatment. Mastitis that does not respond to treatment should be investigated further with biopsy to ensure correct diagnosis;

Lipoma – a benign tumour of fat cells that can occur anywhere in the body. They are common and generally soft and painless.

Some benign breast diseases are not themselves cancerous but can carry a slight increase in the risk of breast cancer in the future. The level of this risk depends on the patient’s medical and family history. These include:

Fibroadenomas – areas of overgrowth of normal breast tissue due to hormonal stimulation that are common in younger women. They are generally painless, soft and mobile. They are removed if larger than 2 cm, growing rapidly, or causing distress to the patient;

Tubular adenomas – benign tumours of cells of breast glands, they are rare but most common in younger women;

Phyllodes tumour – rare tumours of breast tissue that can be difficult to diagnose. They appear similar to fibroadenomas but have a greater tendency to recur. Rarely, a Phyllodes tumour can be cancerous and spread to distant tissues and are therefore surgically removed if diagnosed.

Many other rare conditions can present as a breast lump. For further information, see your family doctor.

Malignant causes of breast lumps

Breast cancer is the most common cancer in women (excluding skin cancers) and second most common cause of cancer deaths in women. The main risk factors for the development of breast cancer include age, age at first menstruation, age at first childbirth, hormonal factors, family history and a history of abnormal breast biopsies.

Breast cancer can first present as a palpable breast lump (can be felt by pressing a hand on the site) and may be painless. Any changes in breast or skin appearance, nipple discharge, nipple inversion and breast pain should be reported to your family doctor for further investigation.

Breast cancer is broadly classified as ductal (originating from the milk ducts inside the breast) or lobular (originating from the breast tissue surrounding the ducts). Breast cancer is preceded by a series of stages of cellular change; normal breast cells take an abnormal shape (atypical hyperplasia), develop into localised areas of cancerous cells (carcinoma-in-situ) and then into frank breast cancer that can spread to other areas of the body. These changes are also classified by the area (ductal or lobular), hence the terms ductal carcinoma-in-situ (DCIS) and lobular carcinoma-in-situ (LCIS). Approximately 80% of breast cancers are ductal in origin and 12% are lobular, with the remaining cases are made up by the more rare causes of breast cancer.

Rare types of breast cancer include lymphoma of the breast, spread of cancer from other tissues to the breast (such as from small bowel cancer) or cancers of the blood vessels within the breast (mammary angiosarcoma).

History

Although many breast lumps are not breast cancer, all patients presenting with a breast lump should be investigated thoroughly to exclude the possibility. In the case of a new breast lump, your doctor will take a medical history and perform a complete physical examination. Your doctor can also instruct you in how to perform breast self-examination.

Your family history, that is; relatives with breast problems or breast cancer.

Examination

A complete breast examination should include both breasts, nipples and surrounding lymph nodes, as well as a thorough general examination. The aim of the examination is to detect any signs suggestive of breast cancer or other breast conditions. A clinical examination should assess the size, shape, consistency, mobility and tenderness of the breast lump, nature of the breast tissue and the presence of any palpable lymph nodes. Feeling a breast lump can be quite challenging, as all breasts have variable combinations of glands, fibrous tissue and fat, and many women have naturally lumpy breasts.

Investigations

After a thorough history and physical examination, your doctor may refer you for special tests to determine the cause of the breast lump. The use of various investigations depends on the history and examination findings. For example, mammography is less effective an investigation in younger women. The aim of these investigations is to accurately separate benign from malignant breast diseases.

Mammography

A mammogram uses low-energy x-rays to image the breast. For a woman over 30 years old presenting with a new breast lump a mammogram is an appropriate first investigation. It is also used in screening for breast cancer to detect breast lumps that cannot be felt. While a mammogram can identify suspicious features in a breast lump, it cannot determine whether a lump is benign or not.

Ultrasound

Ultrasound is an appropriate first investigation for women who are under 30 years old or pregnant and have a breast lump. It is also useful in patients with a palpable breast lump and an abnormal mammogram result. Ultrasound can demonstrate if a mass is cystic or solid and can also be used to guide aspiration (e.g. for treatment of a breast cyst) or biopsy.

Breast Magnetic Resonance Imaging (MRI)

In the case of uncertain imaging findings, MRI can be used to image the breast. However, it is not used routinely due to a high number of false positive results.

Tissue Sampling – Fine Needle Aspiration (FNA)

Taking a tissue sample of a breast lump allows a more definitive diagnosis as the cells can be examined directly. Fine needle aspiration (FNA) is a minor procedure, where local anaesthetic is used to numb an area of breast tissue and a FNA needle inserted into the breast lump and the syringe plunger is drawn out (aspirated) to obtain a sample of cells. The tissue or fluid sample taken can be examined for the presence of any cancerous cells. FNA can also be used to treat a breast cyst, by aspirating the fluid inside the cyst itself.

Tissue Sampling – Core Needle Biopsy (CNB)

Core needle biopsy (CNB) is a more invasive procedure than FNA, but is superior to FNA in the detection of breast cancer. It uses a larger, hollow needle that allows better sampling of the tissue within the lump, which can then be examined for malignancy. CNB is guided by mammography or ultrasound to ensure the breast lump is accurately sampled.

Treatment

The appropriate management of a breast lump requires the use of a medical history, examination and investigations to establish a likely diagnosis. While common, benign breast diseases should always be investigated thoroughly until breast cancer can be confidently excluded.

The “triple test” is a combination of physical examination, breast imaging (usually mammography) and biopsy (FNA or CNB) to calculate a triple test score. Triple test scores can reliably separate benign from malignant causes of breast lumps. Triple testing is essential for women with a breast lump. Once a breast lump is confirmed as benign, specific treatment may not be necessary. Ongoing surveillance of a breast lump is recommended so any changes in the lump can be detected as early as possible.

If a breast lump is confirmed as showing malignant features, the most appropriate treatment depends on the degree of local invasion and whether the cancerous cells have spread to other areas of the body. This generally requires the use of other investigations, such as a CT or lymph node biopsy.

The appropriate treatment for breast cancer depends on the type and stage of the cancer, as well as the patients’ age, health and wishes. Generally, treatment for early, localised breast cancer can involve surgery (such as a lumpectomy or mastectomy and/or radiation therapy. If cancerous cells have spread to other areas, treatment may also involve chemotherapy agents or other medications. However, the choice, timing, disadvantages and advantages of various treatment strategies depend on a patient’s individual circumstances and should be discussed in detail with your treating physician.

This article was kindly reviewed by Winthrop Professor Christobel Saunders.

More information

For more information on breast cancer, types of breast cancer and its investigations and treatments, as well as some useful videos, see